<!DOCTYPE html>
<html>
<head>
  <title>地图导航</title>
  <style>
    #map {
      width: 400px;
      height: 400px;
    }
  </style>
</head>
<body>
  <div id="map"></div>
  <script src="https://maps.googleapis.com/maps/api/js?key=KfIViW4OS7dUlHSlKpuDqceeiMuUzO8d&callback=initMap" async defer></script>
  <script src="script.js"></script>
</body>
</html>